The present invention relates to bistable circuits, and more particularly, it relates to high gain enhancement mode field-effect transistor (FET) bistable multivibrator circuits.
While there are many forms of bistable circuits existing in the prior art, there are none which are as well adapted for a double ended mode of operation as that of the present invention. A double ended mode of operation means that the bistable circuit is responsive to an input signal on each of its sections and makes a decision as to which of the input signals is greater based on a small voltage difference existing between the two signals.
Most prior art bistable circuits respond to a single ended decision making process that one signal is greater than the opposite signal. In a single ended process, the input signal having the greater voltage level is normally the one that is turned on. Such a single ended mode of operation is best adapted for operation where the voltage difference between the two input signals is large. It is not so well adapted to make a decision where the voltage difference is rather small.
Accordingly, in the present invention the input signals to the bistable multivibrator are compared and their voltage difference is used to dynamically drive each of the two sides of the bistable multivibrator into conduction to indicate which of the input signals is larger than the other. In doing this, a unique cross-coupling and driving approach is beneficial in achieving a degree of discrimination between the input signals heretofore not possible in the prior art.